U.S. patent application number 11/572182 was filed with the patent office on 2008-08-14 for coolant conditioning unit comprising a non-return valve.
This patent application is currently assigned to HENGST GMBH & CO. KG. Invention is credited to Richard Eberle, Ludger Schachtrup.
Application Number | 20080190832 11/572182 |
Document ID | / |
Family ID | 35063074 |
Filed Date | 2008-08-14 |
United States Patent
Application |
20080190832 |
Kind Code |
A1 |
Schachtrup; Ludger ; et
al. |
August 14, 2008 |
Coolant Conditioning Unit Comprising A Non-Return Valve
Abstract
Coolant conditioning unit for coolant of an internal combustion
engine. The unit includes a cup-shaped housing, a removable cover
for closing the housing, a replaceable filter insert arranged in
the housing and being detachably connected to the cover, an inlet,
an anti-drain valve that is normally open during filtering, and a
stop valve arranged in the inlet. The stop valve is held in an open
position by the filter insert and closes when the filter insert is
removed from the housing and closes before the cover has been
completely separated from the housing. This abstract is not
intended to define the invention disclosed in the specification,
nor intended to limit the scope of the invention in any way.
Inventors: |
Schachtrup; Ludger;
(Muenster, DE) ; Eberle; Richard; (Muenster,
DE) |
Correspondence
Address: |
GREENBLUM & BERNSTEIN, P.L.C.
1950 ROLAND CLARKE PLACE
RESTON
VA
20191
US
|
Assignee: |
HENGST GMBH & CO. KG
Muenster
DE
|
Family ID: |
35063074 |
Appl. No.: |
11/572182 |
Filed: |
July 13, 2005 |
PCT Filed: |
July 13, 2005 |
PCT NO: |
PCT/DE05/01240 |
371 Date: |
November 27, 2007 |
Current U.S.
Class: |
210/234 ;
210/235 |
Current CPC
Class: |
B01D 35/153 20130101;
F01P 11/06 20130101; F01P 2011/061 20130101 |
Class at
Publication: |
210/234 ;
210/235 |
International
Class: |
F01P 11/00 20060101
F01P011/00; F01P 11/06 20060101 F01P011/06; B01D 35/02 20060101
B01D035/02 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 14, 2004 |
DE |
20 2004 011 104.7 |
Nov 16, 2004 |
DE |
20 2004 017 745.5 |
Claims
1-8. (canceled)
9. A coolant conditioning unit for coolant of an internal
combustion engine, the unit comprising: a cup-shaped housing; a
removable cover for closing the housing; a replaceable filter
insert arranged in the housing and being detachably connected to
the cover; an inlet; an anti-drain valve that is normally open
during filtering; and a stop valve arranged in the inlet, wherein
the stop valve is held in an open position by the filter insert and
closes when the filter insert is removed from the housing and
closes before the cover has been completely separated from the
housing.
10. The unit of claim 9, wherein the inlet is adapted to receiving
unfiltered coolant and further comprising a return line guiding
filtered coolant to a coolant circuit.
11. The unit of claim 9, wherein the anti-drain valve is arranged
in a return line and the stop valve is a path-actuated stop
valve.
12. The unit of claim 9, wherein the filter insert is essentially
cylindrical and comprises an end plate, the end plate being
arranged adjacent to the stop valve and being structured and
arranged to cause movement of a valve body of the stop valve.
13. The unit of claim 9, wherein the stop valve comprise a tappet
that connects to a valve body and has one end that extends up to a
end plate of the filter insert.
14. The unit of claim 9, wherein the filter insert comprises an end
plate having a guide groove adapted to guide a tappet of the stop
valve.
15. The unit of claim 9, wherein the filter insert comprises an end
plate having a strengthened area which acts on the stop valve.
16. The unit of claim 9, wherein the filter insert comprises an end
plate having a perimeter bulge.
17. The unit of claim 9, further comprising a seal arranged between
the cover and the housing.
18. The unit of claim 17, wherein the cover and the housing overlap
over a certain distance, whereby a overlap area is reduced when the
cover is removed from the housing, whereby the stop valve assumes a
closed position while the cover and the housing remain in an
overlapping position, and whereby the seal provides sealing after
the stop valve closes.
19. The unit of claim 9, wherein the cover and the housing are
threadably connected to each other.
20. The unit of claim 9, wherein the stop valve moves to the closed
position via one of a spring and pressure that is greater than a
pressure in the housing.
21. A coolant conditioning unit for coolant of an internal
combustion engine, the unit comprising: a housing; a removable
cover; a replaceable filter insert arranged in the housing; an
inlet; an anti-drain valve that is normally open during filtering;
and a stop valve that assumes an open position when the filter
insert is arranged in the housing, closes when the filter insert is
removed from the housing, and closes before the cover has been
completely separated from the housing.
22. The unit of claim 21, wherein the cover and the housing overlap
over a certain distance, whereby a overlap area is reduced when the
cover is removed from the housing, whereby the stop valve assumes a
closed position while the cover and the housing remain in an
overlapping position, and whereby a seal provides sealing after the
stop valve closes.
23. The unit of claim 21, wherein the stop valve moves to the
closed position via one of a spring and pressure that is greater
than a pressure in the housing.
24. A coolant conditioning unit for coolant of an internal
combustion engine, the unit comprising: a housing; a removable
cover that can be removed without causing coolant from flowing out
of the housing; a replaceable filter insert arranged in the
housing; an inlet; an anti-drain valve that is normally open during
filtering; and a stop valve that assumes an open position when the
filter insert is arranged in the housing, closes when the filter
insert is removed from the housing, and closes before the cover has
been completely separated from the housing.
25. The unit of claim 24, wherein the cover and the housing overlap
over a certain distance, whereby a overlap area is reduced when the
cover is removed from the housing, whereby the stop valve assumes a
closed position while the cover and the housing remain in an
overlapping position, and whereby a seal provides sealing after the
stop valve closes.
26. The unit of claim 24, wherein the stop valve moves to the
closed position via one of a spring and pressure that is greater
than a pressure in the housing.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a U.S. National Stage of
International Patent Application No. PCT/DE2005/001240 filed Jul.
13, 2005 which published as WO 2006/005331 on Jan. 19, 2006, and
claims priority of German Patent Application Nos. 20 2004 011 104.7
filed Jul. 4, 2004 and 20 2004 017 745.5 filed on Nov. 16,
2004.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to a coolant conditioning unit for the
coolant of an internal combustion engine.
[0004] 2. Discussion of Background Information
[0005] Coolant conditioning units of this type are known from
practice. On the one hand, they make it possible to extend the
useful life of the coolant by filtering it. With conditioning units
of this type it is furthermore customarily provided to use a
cartridge with conditioning agent when changing the filter insert.
This cartridge is automatically opened when the filter insert is
inserted into the housing and adds conditioning additives into the
coolant circuit, e.g., so-called "inhibitors," which can serve,
e.g., as antifreeze and corrosion inhibitor.
[0006] With coolant conditioning units of this type, the so-called
filter change, i.e., the change of the filter insert, often takes
place when the coolant still has a relatively high temperature, and
the coolant system is under pressure.
SUMMARY OF THE INVENTION
[0007] The invention aims to improve a generic coolant conditioning
unit to make it possible to change the filter insert safely and, in
particular, to open the coolant filter safely.
[0008] In other words, the invention provides for closing off the
interior of the filter housing with respect to the remaining
coolant circuit, so that excess pressure prevailing in the coolant
circuit cannot cause hot coolant to leak or spurt out of the filter
housing when the cover is removed from the housing. The pressure
prevailing in the filter housing itself is relieved in that the
cover is removed, and the coolant located in the filter housing can
decompress in the meantime before the cover is removed completely,
and the sealing bond between cover and housing is broken.
[0009] There is a shut-off with respect to the remaining coolant
circuit at two points, namely at the coolant supply and at the
coolant return line. A check valve can be provided in this return
line, so that during normal operation--driven by the coolant
pump--a higher pressure prevails on the clean side of the coolant
filter than in the remaining coolant circuit, whereby the
"remaining coolant circuit" is understood within the scope of the
present invention to be the sections of the coolant circuit that
connect directly to the mentioned valves provided according to the
invention. During normal operation the check valve opens as a
result of the pressure difference. During a filter change, or when
the coolant filter is opened for other reasons, and the pressure in
the filter interior is relieved, a lower pressure prevails there
than in the remaining coolant circuit, so that the mentioned check
valve closes in the return line.
[0010] A stop valve is provided in the inlet. The stop valve does
not open or close in a pressure-actuated manner, but does so
instead in a path-actuated manner. The filter insert pushes the
movable valve body of this stop valve into its open position. If
the cover is removed from the housing, the filter insert is thereby
also moved at the same time. The insert is connected to the cover,
e.g., by a clip connection. This movement of the filter insert also
reduces the impingement with which the filter insert acts on the
valve body of the stop valve. The valve body can be guided into its
closed position, e.g., in a spring-loaded manner. As the cover is
removed from the housing of the filter, the filter insert is
correspondingly moved as well. Instead of the above-mentioned
spring, a movement of the valve body can also be provided solely by
way of the pressure prevailing in the remaining coolant circuit, so
that the stop valve is no longer forced to remain open when the
filter insert is removed from the valve body, but can be pushed
into its closed position, following the pressure in the coolant
circuit.
[0011] Advantageously, the filter insert can be embodied in a
manner known per se as an approximately cylindrical insert with an
upper end plate, which has, e.g., the snap-in connection with the
cover, and with a lower end plate, which bears against the valve
body as a pressure plate or acts directly or indirectly on the
valve body and pushes it into its open position when the filter
insert is in its operating position.
[0012] Advantageously, a tappet can be provided that connects to
the valve body and extends up to the end plate of the filter
insert. In this manner, an arrangement of the valve body and the
corresponding sealing surface of the stop valve can be provided at
an appropriate position without any problems. This position
potentially is at a distance from the end plate of the filter
insert, whereby the tappet spans this distance and renders possible
the impingement of the valve body by the end plate.
[0013] The above-mentioned end plate can preferably be strengthened
in the area that acts on the stop valve. The end plate can thus
basically be embodied in a material-saving manner, while it is
reinforced only in the necessary area that acts on the stop valve,
so that a reliable actuation of the stop valve is ensured, and
deformations of the end plate, as may occur at the temperatures and
pressures prevailing during operation, are ruled out.
[0014] The above-mentioned strengthening of the end plate can be
effected, e.g., by a perimeter bulge.
[0015] Advantageously, an amount of overlap that is initially
unnecessarily large for structural reasons can be provided between
the cover and the housing of the filter. Under the usual operating
conditions, a seal ensures the reliable tightness between cover and
housing. Through the large overlap area, this tightness is still
ensured, even when the cover has already been partially removed
from the housing. In this manner, a movement clearance is created
for the cover, which clearance can be used to close the stop valve
during this movement and at the same time reliably seal the
interior of the filter to the outside, i.e., towards the user, so
that the user is reliably protected from leaking coolant. Only
after a distance that has reliably caused the closing of the stop
valve does the cover come clear of the housing far enough for the
seal to be no longer effective between cover and housing. However,
an unexpected leaking of pressurized coolant from the filter
interior is no longer possible in this position of the cover,
because the stop valve and the check valve actuated in a
pressure-dependent manner have closed off the filter interior with
respect to the remaining coolant circuit, so that the filter insert
can now be removed safely.
[0016] The invention also provides for a coolant conditioning unit
for coolant of an internal combustion engine, wherein the unit
comprises a cup-shaped housing, a removable cover for closing the
housing, a replaceable filter insert arranged in the housing and
being detachably connected to the cover, an inlet, an anti-drain
valve that is normally open during filtering, and a stop valve
arranged in the inlet. The stop valve is held in an open position
by the filter insert and closes when the filter insert is removed
from the housing and closes before the cover has been completely
separated from the housing.
[0017] The inlet may be adapted to receiving unfiltered coolant and
further comprising a return line guiding filtered coolant to a
coolant circuit. The anti-drain valve may be arranged in a return
line and the stop valve is a path-actuated stop valve. The filter
insert may be essentially cylindrical and may comprise an end
plate, the end plate being arranged adjacent to the stop valve and
being structured and arranged to cause movement of a valve body of
the stop valve. The stop valve may comprise a tappet that connects
to a valve body and has one end that extends up to a end plate of
the filter insert. The filter insert may comprise an end plate
having a guide groove adapted to guide a tappet of the stop valve.
The filter insert may comprise an end plate having a strengthened
area which acts on the stop valve. The filter insert may comprise
an end plate having a perimeter bulge. The unit may further
comprise a seal arranged between the cover and the housing. The
cover and the housing may overlap over a certain distance, whereby
a overlap area is reduced when the cover is removed from the
housing, whereby the stop valve assumes a closed position while the
cover and the housing remain in an overlapping position, and
whereby the seal provides sealing after the stop valve closes. The
cover and the housing may be threadably connected to each other.
The stop valve may move to the closed position via one of a spring
and pressure that is greater than a pressure in the housing.
[0018] The invention also provides for a coolant conditioning unit
for coolant of an internal combustion engine, wherein the unit
comprises a housing, a removable cover, a replaceable filter insert
arranged in the housing, an inlet, an anti-drain valve that is
normally open during filtering, and a stop valve that assumes an
open position when the filter insert is arranged in the housing,
closes when the filter insert is removed from the housing, and
closes before the cover has been completely separated from the
housing.
[0019] The cover and the housing may overlap over a certain
distance, whereby a overlap area is reduced when the cover is
removed from the housing, whereby the stop valve assumes a closed
position while the cover and the housing remain in an overlapping
position, and whereby a seal provides sealing after the stop valve
closes. The stop valve may move to the closed position via one of a
spring and pressure that is greater than a pressure in the
housing.
[0020] The invention also provides for a coolant conditioning unit
for coolant of an internal combustion engine, wherein the unit
comprises a housing, a removable cover that can be removed without
causing coolant from flowing out of the housing, a replaceable
filter insert arranged in the housing, an inlet, an anti-drain
valve that is normally open during filtering, and a stop valve that
assumes an open position when the filter insert is arranged in the
housing, closes when the filter insert is removed from the housing,
and closes before the cover has been completely separated from the
housing.
[0021] The cover and the housing may overlap over a certain
distance, whereby a overlap area is reduced when the cover is
removed from the housing, whereby the stop valve assumes a closed
position while the cover and the housing remain in an overlapping
position, and whereby a seal provides sealing after the stop valve
closes.
[0022] The stop valve may move to the closed position via one of a
spring and pressure that is greater than a pressure in the
housing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Exemplary embodiments of the invention are explained below
in more detail on the basis of the purely diagrammatic drawings
wherein:
[0024] FIG. 1 shows an overall cross section through a coolant
conditioning unit of a first exemplary embodiment;
[0025] FIG. 2 shows an area of the stop valve of the unit of FIG. 1
on a larger scale with respect to FIG. 1;
[0026] FIGS. 3 and 4 show views similar to FIGS. 1 and 2, but of a
second exemplary embodiment; and
[0027] FIGS. 5 and 6 show views similar to FIGS. 1 and 3, but of a
third exemplary embodiment, with two positions of the cover
unscrewed to different extents.
DETAILED DESCRIPTION OF THE INVENTION
[0028] FIGS. 1 and 3, respectively show a coolant conditioning unit
1. This unit has a cup-shaped housing 2 and a cover 3 embodied as a
screw cover and screwed together with the housing 2. A perimeter
O-ring seal 4 is provided between cover 3 and housing 2. The cover
3 has a displacement body 5 which makes it impossible for the
interior of the housing 2 to be completely filled with coolant.
When the cover 3 is removed from the housing 2, the liquid level in
the interior of the housing is thus automatically lowered, so that
even when the housing 2 is inclined to an extent customary during
operation, it is ensured that no coolant can flow off over the
upper edge of the housing 2, but remains reliably within the
housing 2.
[0029] A filter insert 6 is connected to the cover 3, namely via a
snap-in connection 7 provided on an upper end plate 8 of the filter
insert 6 embodied overall to be essentially cylindrical. The filter
insert 6 has a filter medium 9 in the form of, e.g., a folded paper
filter, and an inner support dome 10 featuring openings 11. At its
lower end, the filter insert 6 has a lower end plate 12.
[0030] The coolant flows through an inlet 14 radially outside the
filter insert 6 into the housing 2. After passing through the
filter medium 9, the coolant reaches the interior of the filter
insert 6 and flows back there through a return line 15. A check
valve 16 with a valve body embodied as a sphere 17 is provided in
the return line 15. The check valve 16 is embodied as a so-called
float valve. In the operating state depicted in the drawing, the
sphere 17 bears against a lower stop 18. It can be lifted and
pressed against its valve seat through the effect of its buoyancy
and through the pressure prevailing in the remaining coolant
circuit when the pressure prevailing in the interior of the housing
2 and in particular in the interior on the clean side of the filter
insert 6 is correspondingly low with respect to the pressure in the
remaining coolant circuit below the sphere 17.
[0031] A stop valve 19 visible in more detail in particular in
FIGS. 2 and 4 is provided in the inlet 14. This stop valve has a
movable valve body 20 and a collar-shaped valve seat 21. The valve
body 20 is connected to a tappet 22 against which the lower end
plate 12 bears. In the exemplary embodiment of FIGS. 3 and 4, the
lower end plate 12 is strengthened and thus reinforced along its
outer circumference by a lower perimeter bulge 23, so that it does
not deform under the pressure of the tappet 22 and allow an
inadmissible closing movement of the stop valve 19.
[0032] Furthermore, the bulge 23 embodies a guide groove 25 in
which the upper end of the tappet 22 is guided.
[0033] The closing movement of the stop valve 19 is made possible
when the cover 3 is screwed out of the housing 2. In this case,
with the alignment of the housing 2 provided in the drawing, the
filter insert 6 together with the cover 3 moves upward as well.
With a corresponding preloading of the stop valve 19, the tappet 22
and thus the valve body 20 can follow this movement, so that the
valve body 20 comes closer to the valve seat 21, the further the
cover 3 is loosened from the housing 2.
[0034] The mentioned preloading of the stop valve 19 can either be
effected by a spring 24, whereby the valve body 20 is held in its
open position by the filter insert 6 against the effect of this
spring 24, or the preloading mentioned can be realized by the
pressure prevailing in the remaining coolant circuit, which
pressure is higher than the pressure prevailing in the housing 2,
in particular if the effective interior volume of the housing 2 is
enlarged by unscrewing the cover 3.
[0035] Because of this pressure difference the valve body 20 is
pressed into its closed position, even if the spring 24 shown were
not present. However, should the housing 2 be opened when the
coolant is cold and thus without pressure, the stop valve 19 would
not be closed if the valve body 20 were pushed into its closed
position exclusively due to the interior pressure in the coolant
circuit. In a case of this type, however, there would be no fear of
the hot coolant suddenly leaking out either, so that there would be
an automatic, temperature-dependent and self-regulating action of
the stop valve 19.
[0036] Irrespective of whether the spring 24 provided in the
drawing is present or not, the stop valve 19 is a path-actuated
valve, since the open position of the valve body 20 is forced in
any case depending on the displacement of the position of the
filter insert.
[0037] The arrangement of the seal 4 provided on the cover 3 is
provided spaced so far apart from the upper edge of the housing 2
that this distance is larger than the path the valve body 20 has to
travel from its open position depicted to its closed position. It
is thus ensured that the stop valve 19 is closed when the seal 4 is
still effective in a sealing manner during the removal of the cover
3 from the housing 2. Only in the further course of this removal
movement of the cover 3 does the seal 4 reach the upper edge of the
housing 2 and lose its effectiveness. In this case, however, the
check valve and stop valve 16 and 19 are closed, and it is also
reliably ensured because of the displacement body 5 that excess
pressure no longer prevails in the interior of the housing 2
shortly before the seal 4 loses its effectiveness, which excess
pressure could lead to a sudden leaking of hot coolant.
[0038] In the exemplary embodiment of FIGS. 5 and 6, identical or
identically acting component parts are provided with the same
reference numbers as in the exemplary embodiments of FIGS. 1
through 4. Reference is made below only to those features that
differentiate this third exemplary embodiment from the other two
exemplary embodiments, so that only the units or components
relevant in connection therewith are mentioned and provided with
reference numbers in the drawings.
[0039] FIG. 5 shows a third exemplary embodiment in the state ready
for operation, i.e., with the cover 3 completely screwed into the
housing 2. The displacement body 5 is thereby not provided radially
outside the filter insert 6, but exclusively above the upper end
plate 8 of the filter insert 6. The radial constructed space within
the housing 2 can thus be utilized optimally, so that either a
filter insert 6 with very wide folds can be used, or the diameter
of the housing 2 can be kept comparatively small, and can still be
arranged at an optimum location even under conditions of limited
space. Although the axial extension of the coolant conditioning
unit 1 is enlarged by shifting the displacement body 5 axially in
front of the filter insert 6, there is, however, usually enough
free space available in this direction, since the cover 3 is
provided to be accessible anyway in this direction for maintenance
tasks.
[0040] In the exemplary embodiment of FIGS. 5 and 6, a vent line 26
is realized in the cover 3, which vent line leads to a
corresponding air vent 27 in the upper end plate 8 of the filter
insert 6. Advantageously in terms of production technology, the
vent line 26 is not realized by a bore, but by one or more ribs on
the underside of the cover 3, where the cover 3 forms the displacer
body 5. Alternatively, vent lines of this type can be realized by
recesses, i.e., creases in the lower edge of the cover 3, or also
by corresponding ribs or creases in the surface of the upper end
plate 8. In any case, the vent line 26 represents a short circuit,
i.e., a bypass of the filter insert 6, so that unclean coolant can
reach the clean side of the filter through the vent bore 27,
bypassing the filter insert 6. But since the filter is designed
merely as a partial-flow filter anyway and merely a part of the
overall recirculated coolant filter, this bypass of the filter
insert 6 does not represent any relevant impairment of the filter
function.
[0041] To the left of the vent line 26, a bore 29 is respectively
visible in FIGS. 5 and 6, which bore extends through the cover 3.
Together with the vent line 26 and the air vent 27 it renders
possible a venting of the housing 2 when the filter insert 6 is
inserted into the housing 2, and the air present in the housing 2
at first is thereby displaced. The air displaced from the housing 2
can escape through the bore 29 until the seal 4 touches the housing
2 and bears against it in a sealing manner.
[0042] In the exemplary embodiment of FIGS. 5 and 6, the stop valve
19 is shown only by way of example to the left of the anti-drain
valve 16, i.e., on the opposite side with respect to the other
exemplary embodiments.
[0043] The valve body 20 of the stop valve 19 is guided through
ribs 28 in the axial direction, whereby these ribs are molded in
the housing 2, so that the guiding of the valve body 20 is ensured
in a technically simple and economically advantageous manner.
[0044] As is revealed, in particular, by the comparison between
FIGS. 5 and 6, the length of the thread between housing 2 and cover
3 and the position of the seal 4 are coordinated with one another
such that the internal and external thread of the housing 2 and the
cover 3 mesh with one another before the sealing ring bears against
its sealing surface provided in the housing 2. When the cover 3 is
screwed into the housing 2, the seal 4 is thus drawn into the
housing 2 as well. On the one hand, this facilitates handling when
the cover 3 is screwed in and furthermore ensures that a kind of
centering of the cover 3 takes place through the thread, so that
the seal 4 bears against the associated sealing surface of the
housing 2 as evenly as possible on the entire circumference, and an
excessive one-sided loading of the seal 4 is avoided, which might
lead to the seal being damaged.
* * * * *